title: Mechanisms of acute respiratory distress syndrome in children and adults: a review and suggestions for future research.
abstract: OBJECTIVE
  To provide a current overview of the epidemiology and pathophysiology of acute respiratory distress syndrome in adults and children, and to identify research questions that will address the differences between adults and children with acute respiratory distress syndrome.
  
  
  METHODS
  Narrative literature review and author-generated data.
  
  
  METHODS
  The epidemiology of acute respiratory distress syndrome in adults and children, lung morphogenesis, and postnatal lung growth and development are reviewed. The pathophysiology of acute respiratory distress syndrome is divided into eight categories: alveolar fluid transport, surfactant, innate immunity, apoptosis, coagulation, direct alveolar epithelial injury by bacterial products, ventilator-associated lung injury, and repair.
  
  
  METHODS
  Epidemiologic data suggest significant differences in the prevalence and mortality of acute respiratory distress syndrome between children and adults. Postnatal lung development continues through attainment of adult height, and there is overlap between the regulation of postnatal lung development and inflammatory, apoptotic, alveolar fluid clearance, and repair mechanisms. Therefore, there is a different biological baseline network of gene and protein expression in children as compared with adults.
  
  
  CONCLUSIONS
  There are significant obstacles to performing research on children with acute respiratory distress syndrome. However, epidemiologic, clinical, and animal studies suggest age-dependent differences in the pathophysiology of acute respiratory distress syndrome. In order to reduce the prevalence and improve the outcome of patients with acute respiratory distress syndrome, translational studies of inflammatory, apoptotic, alveolar fluid clearance, and repair mechanisms are needed. Understanding the differences in pathophysiologic mechanisms in acute respiratory distress syndrome between children and adults should facilitate identification of novel therapeutic interventions to prevent or modulate lung injury and improve lung repair.
authors.affiliation: Division of Critical Care Medicine, Department of Pediatrics, University of Washington and Seattle Children's Hospital, Seattle, WA, USA. lincolns@uw.edu
authors.forename: Lincoln S
authors.initials: LS
authors.lastname: Smith
authors.forename: Jerry J
authors.initials: JJ
authors.lastname: Zimmerman
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Martin
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000502:physiology; D001315:Australia / Q000453:epidemiology; D001777:Blood Coagulation / Q000502:physiology; D002648:Child; D005060:Europe / Q000453:epidemiology; D006805:Human Experimentation; D006801:Humans; D007113:Immunity, Innate; D008168:Lung / Q000254:growth & development / Q000276:immunology / Q000503:physiopathology; D017063:Outcome Assessment, Health Care; D015995:Prevalence; D012128:Respiratory Distress Syndrome / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology; D014481:United States / Q000453:epidemiology; D055397:Ventilator-Induced Lung Injury / Q000150:complications / Q000276:immunology / Q000503:physiopathology